Necropolis – “Misfortune never comes alone” [Campaign 2 – Mission 1]

Hello, I downloaded and installed Heroes 6 and decided to play a new campaign... I completed two missions as Haven, and then more campaigns became available. I started with the Necropolis campaign... I played on the normal difficulty level, captured a second castle, and was simply destroyed, my heroes were torn to pieces by heroes from other castles... :smile21: I thought, "Okay, let's try the easy difficulty level," and the same thing happened... only much faster... Can you advise me on what to do? The enemy has a colossal advantage in troops, and it's simply impossible to defeat them... :( Give me some advice on how to complete the campaign :( Game version: Might & Magic Heroes VI Shades of Darkness 2.1.0